This invention relates to a method of making a solid electrolytic capacitor in which a valve metal powder ink is screen printed on a valve metal substrate to form an array of pads, a valve metal pellet is placed on end on each pad, and the assembly is sintered producing a porour metal pellet array bonded through a graded density layer to the substrate. The assembly is then anodized to form a valve metal oxide over its surfaces and processed to form an array of solid electrolyte capacitors which may then be separated into individual capacitors.
Solid electrolytic capacitors have been made by screen printing multiple layers of tantalum onto a substrate, sintering, and processing into capacitors. Still others have been made by pressing and sintering powder pellets onto substrates and then processing to form solid electrolyte capacitors. However, pellets made from the high CV powders currently available have lower densities than those of the prior art and can not be adequately compressed onto a substrate to form any sort of a bond therebetween. While it is possible to screen print multiple layers of these high CV powders to form capacitors, the long dimension of the resulting body lies in the plane of the substrate which limits the numbers of anodes processed per batch.